Immobilized after lost chip/damaged key?

My only key fob was damaged which has apparently forced the car into immobilizer mode. From the research I've done thus far it seems the chip is missing, which is possible given that the fob broke into a few pieces. Initially I intended to purchase an immobilizer bypass module yet I'm leaning towards a new key fob instead and programming it to the vehicle myself. With that being said, I'm afraid this may not resolve the issue. Any suggestions? Please help, I've been immobilized for months now!